Test–retest reliability and minimal detectable change of pulse wave velocity and flow‐mediated dilation in paretic and non‐paretic limbs of older adults post‐stroke

Abstract

Arterial stiffness and endothelial dysfunction are non‐traditional risk markers after stroke, yet reliability and minimal detectable change (MDC) of pulse wave velocity (PWV) and flow‐mediated dilation (FMD) have not been established. We examined test–retest reliability and MDC of carotid‐femoral (cfPWV), carotid‐radial (crPWV), and femoral‐dorsalis pedis PWV (ffPWV), and absolute and relative brachial artery FMD in people >12 months post‐stroke. Seventeen individuals ( n  = 4 (24%) females; 63.9 ± 8.6 years; 4.5 ± 2.8 years post‐stroke) completed two bilateral assessments of PWV via applanation tonometry and FMD via duplex ultrasound within 1 week. Intraclass correlation coefficients (ICC _2,1 ) were calculated via two‐way random‐effects models, and MDC derived at 68%, 90%, and 95% confidence levels. We found good‐to‐excellent reliability for cfPWV in paretic (ICC _2,1  = 0.85; 95% CI:0.59, 0.95) and non‐paretic (ICC _2,1  = 0.94; 95% CI:0.82, 0.98) limbs, with MDC _95% values of 2.23 and 1.68 m/s, respectively. crPWV and ffPWV exhibited poor reliability bilaterally (ICC _2,1  = 0.12–0.33). Relative FMD showed moderate reliability for paretic (ICC _2,1  = 0.50; 95% CI: −0.20, 0.85) and non‐paretic (ICC = 0.59; 95% CI:0.04, 0.84) limbs, with MDC _95% values of 6.88% and 7.65%, respectively. Reliability for absolute FMD was poor (ICC _2,1  = 0.11–0.44). These findings support cfPWV as a reliable vascular assessment in individuals >12 months post‐stroke, and provide stroke‐specific MDC values to guide interpretability in future trials.